[BUG] Claude Code session blinks if started from Claude Agents on windows (all terminals bash, powershell)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Problem

Terminal blinks in once second 5 times when session started from claude agents on windows in any terminal (powershell, git bash for windows, batch)

Problem started with version 2.1.144

What Should Happen?

Session should not blink

Error Messages/Logs

No error messages

Steps to Reproduce

1. Run claude agents
2. Start session which would work for at least 5 minutes
3. Enter the session
4. Session terminal starts "blinking"

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.144

Claude Code Version

2.1.144

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_